Lock



S MILLER Nov. 14, 1939.

LOCK

' s Sheets-Sheet 2 Filed April 1, 1936 R. v m m 5 m l S. MILLER Nov. 14, 1939.

LOCK

Filed April 1, 1936 3 Sheets-Sheet 5 in a. I.

' ATTORNEY.

Patented Nov. 14, 1939 UNITED STATES PATENT OFFEE 20 Claims.

This invention relates to a lock with special provisions against unauthorized operation (picking), also commonly called a pick-proof look.

A person picking a lock relies on his eye, ear

or touch, and principally upon the latter sense, in trying to open a look. In exploring a cylinder tumbler lockthe type of a lock in connection with which I shall exemplarily explain my inventionhe will feel out the yield or play, no matter how little it amounts to, which indicates success to him when he has shifted the one or the other and then all of the tumbler pins into the correct position. The slightest give or click is sufficient indication, for a person experienced in picking locks, that is making progress in exploring the combination of a lock.

It is the principal object of this invention to remove from the reach and touch of a person trying to pick a lock those tell-tale indications and reactions, which oifer him so much help in his task. With. the ordinary lock step by step, or as a whole, the cylinder of the lock approaches the operative position, increased operability betraying progress in the lock-picking operation.

According to this invention, such increased operability may occur but is in no way betrayed in connection with a lock of my invention, while the operator inserts and manipulates the key.

Operation becomes only possible, after direct communication of the hands of the operator with the tumblers has been severed.

This invention is made possible by closing the key-hole, so that the key therein is disconnected from the outside before the tumbler pins actually function, are disengaged and release the plug or barrel, precisely speaking. Thus I may slide a cover plate over the key-hole, or slide the keyhole behind such a plate, in order to remove it from the physical control of the operator and only then the actual opening operation takes place.

It is understood, that under these circumstances the key actually disappears in the key- 4,5 hole before it opens the lock, and various collateral improvements, the insertion and the removal of the key from the key-hole for instance, means facilitating this operation, and other incidental sectioned mounting, the bolt and case being indicated therebehind in broken lines.

Fig. 2 shows a corresponding top view.

The view of Fig. 3 is similar to that of Fig. 1. But here a key is shown to be inserted in the lock, and the operation has been started, whereas Figure 1 shows the lock in its normal position, when not in use.

Fig. 4 shows a front view of the lock of Fig. 1. The section, along which Fig. 1 is taken, is indicated by a broken section line, arrows, and the numerals I.

Fig. 5 shows a front detail View, the plug or barrel of my lock.

Fig. 6 shows a corresponding cross-sectioned side view.

Fig. '7 shows the handle cover superimposed upon the plug or barrel of my invention This is a front view.

Fig. 8 shows a partly cross-sectioned side view corresponding to the view of Fig. '7.

Figs. 9 and 10, 11 and 12, 13 and 1 .1, and 15 and 16, show the handle cover and the plug or barrel, respectively, in successive positions of operation. All these views are front views.

The views of Figs. 9 and 10 correspond substantially to those of Figs. 5 and 7, showing the respective parts in their normal position.

In'Figs. 11 and 12 the handle cover has been started to turn so that it covers up the key-hole. But the plug or barrel has not moved yet.

In the view of Fig. 13 the handle cover has been further advanced, to a position where it is about to engage upon the plug or barrel, which, however, is still in its normal position, as shown in Fig. 14.

In Fig. 15, the handle cover has engaged upon the plug or barrel, and has moved together therewith through a vector of actual operation of the lock and bolt, after the position of the handle cover has been advanced from that of Fig. 13 to that of Fig. 15.

Fig. 17 is a detail top view of a section of the handle cover and of the key inserted therebehind.

Within the scope of my invention a large range of modifications is of course possible, which cannot be treated in detail because it would make this description too prolix.

However I like to point out one particular modification, which represents the converse of the showing of the preceding figures, and which is shown by the following figures.

Fig. 18 shows the front view of a lock.

Fig. 19 shows a corresponding, cross-sectioned side view, the lock being arranged on a mounting.

Fig. 20 shows another front view, in which the plug or barrel has been shifted to an op erative position of alignment of the tumblers.

Figs. 21 and 22 show cross-sectioned front views of the cylinder and plug or barrel, in positions corresponding to those of Figs. 18 and 20, respectively.

Fig. 23 shows a top view of the plug or barrel only.

Fig. 24 shows a cross-sectioned bottom view of the cylinder only, the view being taken in the direction and in accordance with the arrows and broken lines marked by the numeral 24 in Fig. 22.

Fig. 25 shows the side elevation of a key used in connection with my invention.

Fig. 26 shows an end view of the said key.

Fig. 27 shows another cross-sectioned front view of the cylinder and barrel or plug, incorporating a modification of the barrel or plug and the tumblers contained therein.

Fig. 28 correspondingly indicates the arrangement of another modification.

Similar numerals refer to similar throughout the various views.

In accordance with the general practice in the art of pin tumbler or cylinder locks, my drawings show the cylinder 3| comprising a cylinder sleeve 32 and a sleeve extension 33; by way of a cylinder flange 34 and a back plate 35, the cylinder is clamped onto a mounting 36. A cover plate 3'! finishes the front of the lock.

The cylinder sleeve 32 predeterminedly rotatably accommodates the plug or barrel 38 with the keyway or key slot 39. From the back of the plug or barrel 33 extends the bar 40 to engage the usual roll back for a bolt AI in a lock casing 42. The bar 43 is for instance a T-shaped plate, which is accommodated in the keyway 39 and an exten sion thereof and is there retained by a cover plate 43 with a clearance hole for the bar affixed to the back of the cylinder.

parts The pin tumblers are also shown in a conventional design; the lower parts thereof, the barrel pins 44 are accommodated in the plug or barrel 3B; the upper parts or drivers 45 of the pin tumblers are accommodated in the sleeve extension and are pressed down by compression springs 46 engaged underneath a retaining plate 41 extending across the various pin tumblers in the sleeve extension 33.

A key 48 of my invention is shown in Figs. 3 and 1'7 in side and top views, respectively. Since the key of my invention fully disappears in the lock, there is no handle, but I may provide a perforation 49 or other suitable means for retaining the key on a keyring or for accommodating it otherwise in a receptacle carried by the user. The conventional profile of a key is indicated in the drawings as having a lower extension 53 which imparts an L-shape to the key. It is however understood that any kind of profile commonly used in connection with flat keys may also be used in connection with a key of my invention.

Since the key of my invention fully disappears in the look, I provide means in the lock for automatically ejecting the key, after it has been turned to its original position, in which it had been inserted. I may for instance provide a suitable deeper notch 51, near the front of the key, in Which is engaged the free end of a spring, which is secured in a lateral recess of the keyway in the plug or barrel. Thus I show a lateral recess 55 in the plug or barrel in which the coil spring 52, with the free end 53 engaging in the notch 5| of the key 48, is mounted upon the pin 54, which extends across the plug or barrel 38. In its normal position, the free end 53 of spring 52 (see Fig. 1) extends just below the upper margin of the keyway or slot, so that the key inserted into the key-hole engages at the highest part of its root 55 upon said end, and pushes said end into the notch 5|, said end being swung in counterclockwise direction and being pushed into the lock as the key itself is pushed thereinto. The spring 52 will therefore always have a tendency to eject the key from the keyway and will do so, unless the key is retained in the keyway, and an arrangement for this purpose will be" presently described.

There is a recess in the front of the cylinder extending to a certain depth into the cylinder blank, and arranged concentrically with the plug or barrel 38. In the recess is rotatably accommodated, between the cylinder and the cover plate 31, the flange 58 of the handle cover 51'; the said flange has an opening which substantially corresponds in cross-section with the keyway 39, said opening 59 registering with the keyway in its normal position of rest of Figs. 1, 2 and 4. The handle cover 57 comprises an offset handle 60, which extends through a clearance opening Si in the cover plate 37, said opening the operator cannot insert his finger beyond the flange 58. For that reason I may provide upon the extension 53 of key 43, or upon any other part in the front of said key, a chamfer or bevel 32, and I may bevel oif the flange 58 at the opening 59, in the back thereof, in the manner shown at 63, in order also to propel the key 53 into the lock, beyond the handle cover, after it has been inserted, on turning said cover.

1 It will be seen from a comparison of Fig. 1 and Fig. 3, that the pin tumblers are shifted from an operative position into an inoperative position by the insertion of the correct key in the lock of Fig. 1, because then the tumblers are shifted into the position of Fig. 3, in which they normally would release the barrel or plug. However, in accordance with my invention, I show an additional stop tumbler engaging the barrel or plug 33, aside from the four ordinarily used pin tumblers it, 45. This stop is illustrated as an additional pin tumbler, which comprises the driver 64 in the cylinder and a barrel pin 65 in the plug or barrel, which tumbler is not actuated by the key 38. After the full insertion of the correct key in the lock the four pin tumblers to the right in Fig. 1 will therefore be in the releasing position of Fig. 3, but the pin tumbler 66 is still in the locking position of Fig. 1.

Pin tumbler 36 and more particularly the lower barrel pin part 65 thereof, is superimposed in pin tumbler fashion upon a keyway, not the keyway of the key 48, but keyway 61, which as the sector of a concentric groove extends into the left end of the cylindrical surface of the plug or barrel 38 (Figs. 5 and 6).

A shoulder 68 at the front end of the plug or barrel 38 confronts the groove 61 at a shortened radius, thus permitting a cam 69 extending from the back of the flange 58 of the handle cover 51 to extend into the groove 61, said groove v6T representing a track for the oscillating cam 69, and at the same time offering stops for limiting the angular movement of said cam. Thus the cam 69 may slide in groove Bl between the position of Figs. 9, 11 and 13 of thehandle lock. But in Figs. Band 14 a nose 10 at the right front of cam 69 strikes the right end H of groove 61, so that during further clockwise rotation the handle cover must carry the plug or barrel 38 along from the position of Fig. 14 intothe position of Fig. 16, retracting the bolt 41.

' But before the. plug or barrel 38 can be moved from the position of Fig. 14 into the position of Fig. 16, thepin tumbler 66 must be released. In orderto bring this about, the right front end or nose iii of the cam 69 acts as a key when sliding in the groove or keyway 61in clockwise direction towards the end ll of the keyway. Just before reaching said end H the nose engages underneath the pin tumbler 66 and lifts it from the position of Fig. 1 into the position of Fig. 3,

in which, like the other pin tumblers, pin tumbler iiii now clears and allows rotation of the plug or barrel 38.

The action of my lock is therefore as follows:

After having inserted the key 48 as far as possible into the keyway of the look, i. e., to the extent that the front end of the key is flush with the outside of the flange of the handle cover 51, the operator starts turning the handle cover 51 to the right, and by way of the chamfered end 01' key Q8 and of the chamfered wall of the key-hole 552 in the flange 58 the keyis fully pushed into the lock, but it also has disappeared by now behind the opening 59 in the handle cover.

If the key is the correct key, it lifts after full 'nsertion the pin tumblers M, 45 into the position of release shown in Fig. 3. But the plug or barrel.

38 is still locked in its original position in the cylinder by the pin tumbler 66, so that only the handle cover 51 is rotatable, and it may be rotated through the positions of Figs. 11 and 13, until it finally engages the plug or barrel and lifts the pin tumbler 66 at the same time into they released position. From now on the plug or barrel moves together with the handle cover, during the continued motion of the latter from the position of Fig. 13 to the position of Fig. 15 and the plug or barrel actuates the bolt 4| by way of the bar at.

During the return motion of the handle cover, the procedure is substantially reversed; after the handle cover has been returned to its original position in which itlays free the keyway 39, the key it will be immediately ejected out of the keyway by the action of the spring 52.

It will be understood that the lock of my invention has been rendered practically pick-proof by outwardly covering the keyway in the plug or barrel before the lock actually goes into action. This is brought about by relative movement between the cover 5i and the plug in the foregoing description. While in the modifications so far described, the plug or barrel remained stationary and the cover was moved thereover before the lock went into action, the movement of these parts may be reversed; e. g., there may be a stationary cover plate, which normally clears the keyway in the plug or barrel, but the plug or barrel is moved until the keyway therein has been covered by said cover plate; then the plug is allowed to actuate the lock. This is illustrated in the remaining Figs. 18 to 27.-

While the parts of the old art hereinbefore described in connection with the first modification remain substantially the same, the flange 16 of the cylinder 11 is so large that the cover plate 31 of the prior showing becomes superfluous, said flange 16 being now used to finish the lock in the front, said flange 16 being directly attached to the mounting 3E. The flange 16 also extends over almost one-half of the front of the plug or barrel 38, by way of a segment 18 forming part of the cylinder. An extension of the plug or barrel 38 serves as a handle 19 which protrudes through the opening remaining in the flange 16 adjacent to the segment 8. Underneath the handle 19 is the key-hole 8|. In order to suggest other modifications, which are possible in connection with this invention, the spring 52 is omitted and arbitrarily replaced by a flat spring 82 mounted in posed in the first described modification. Thus the drivers 45 of the pin tumblers are normally out of alignment with the barrel pins 44 of the pin tumblers, because pins 44 and the keyway ordinarily have a vertical position when inactive as shown in the cross-section of Fig. 21. Only after the plug or barrel 38 has'been rotated into alignment with the sleeve extension 33, which the plug or barrel in an upward-extension of the V movement is unchecked, the upper and lower parts ts and i t of the pin tumblers come into alignment and can only then go into action. But by the time the plug or barrel has been shifted from the position of Fig. 21 into the position of Fig. 22, the key-hole or keyway 8! has disappeared behind the segment l8, so'that tampering with the key, as it now goes into action, is impossible.

The drivers ride upon the outer circumference oi, the plug or barrel 38, while the plug or barrel is turned from the position of Fig. 18 or 21 into the position of Fig. 20 or 22. Then they come to rest upon the top of thebarrel pins 44, and arrest further rotation of the plug. or barrel by virtue of being engaged below the outer cira correctkey, the barrel may be swung rightv through the position of Fig. 22 and actuates the bolt it by Way e-f the bar ill, the rim lock .2 being of course set so that said actuationbegins only aftc the plug or barrel has passed the position of 22.

A recess 3 is provided upon the inside at the top of the cylinder in order to clear the barrel pins ii if they are raised by the key above the level. of the outer circumference of the plug or barrel. Another recess 33 is provided in the plug barrel alongside of the barrel pins M at the of the barrel in order to allow the drivers 45 to slide up onto the circumference of the barrel hey have dropped down onto the barrel pins 7 44, when said barrel pins clear the outer cir-' cumference of the barrel for a certain distance, which would indicate that such an improper key has been used. 5 I use a key without a handle also in connection with this departure of my invention, e. g., a key 85 like key 48 shown in the modification of the Figs. 1 to 17. Again this key may be chamfered the front as shown at 86 (Figs. and 26), and the inside of the segments '18 may be chamfered at 8'! (Fig. 24) in order to facilitate full in sertion of the key, after it has been pushed by the finger of the operator as far as possible. If an improper key pushes one or more of the barrel pins "54 above the level of the circumference of the plug or barrel, then the said pins strike the drivers 45 sidewise even before the plug or barrel has been turned by manipulation of handle 19 into the position of Fig. 22. But when the barrel pins 4 3 are too short and do not reach the level of the circumference of the plug or barrel, then the drivers 45 strike the left wall of the hole in which pins 44 are slidably disposed, and arrest the clockwise motion of the plug or barrel t at the position of Fig. 22, in the same manner in which the ordinary lock does not work when the drivers have dropped into the plug or barrel.

If for some reason the pins 44 become stuck in a raised positionin other words if they do not freely drop down onto the key 85-then they will strike in their raised position the sides of the drivers 45, although the correct key might be inserted.

I may make provisions which will prevent such improper functioning of the lock, for instance by reducing clearance 84 by a slant to the right Fig. 28) so that it merges at the roots 94 of the holes in which slide drivers 45 with the inner circular bore 96 of the cylinder sleeve. Thus -10 the slant will push or force down into the plug or barrel the raised barrel pins. If an incorrect key stops the downward movement of the barrel pins, they will jam on the slant, and will prevent the plug or barrel from even reaching the position of Fig. 22. If the correct key is used, the barrel pins will not jam, the drivers come into alignment therewith, but the correct key will prevent the drivers from pressing the level of abutment below the outer circumference of the plug or barrel, so that the plug or barrel swings right through the position of Fig. 22 and the lock is actuated. If the key used is not correct and allows the barrel pin to be pressed by the driver below said circumference, then the driver engaged 55. in the plug or barrel arrests it in the position of 22 and prevents actuation of the look. A modification, which positively presses the bar rel pins down onto the key is indicated in Fig. 27. In Fig. 27 the barrel pins 88 are each provided at their lower ends with a shoulder 89 and the holes 518 accommodating the barrel pins are accordingly enlarged. Onto the top of the shoulder 83 at the bottom of the barrel pins 88 is placed a compression spring 9|, which is retained in the hole Si! by a cover plate 92. The cover plate 92 may be driven welded or otherwise fastened across the length of the plug or barrel or it may be retained in its proper position, because it abuts against the inner bore of the cylinder. The plate 5" is provided with holes guiding the upper ends of pins 96, so that the said pins function in exactly the same manner as the devices shown in Figs.

Clearance openings 93 may also be provided in the cylinder sleeve, as shown in connection with Fig. 27, and may act in addition to the clearance space 84 to allow for the insertion of a key which has high projections near its front. Thus such projections may freely raise and pass underneath long barrel pins.

Having thus described my invention in detail, I do not wish to be limited thereby, except as the state of the art and the appended claims may require, for it is obvious that various modifications and changes may be made in the form of embodiment of my invention, without departing from the spirit and scope thereof.

What I claim is:

1. In a lock having a key for actuating said look, a plug with a keyway for said key, a cover with a movement of play relatively to said plug between a first position in which it outwardly closes said keyway and a second position in which it clears said keyway so that it is outwardly open and said key may be inserted therein, a chamfered portion at the front and one side of said key and engaged by said cover when said key is inserted in said keyway and when said cover and plug are relatively moved from said second into said first position, so that said key is pushed into said keyway behind said cover, and a mechanism normally arresting said movement of play at said first position but releasing said plug when it is actuated by said key.

2. In a look, a key for actuating said look, a plug with a keyway for said key, a cover with a movement of play relatively to said plug between a first position in which it outwardly closes said keyway and a second position in which it clears said keyway so that it is outwardly open and said key may be inserted therein, and a chamfered portion at the back and one side of said cover and engaging said key when said key is inserted in said keyway and when said cover and plug are relatively moved from said second into said first position thus pushing said key back into said keyway.

3. In a look, a cylinder, a plug with a keyway in said cylinder, pin tumblers normally locking said plug in said cylinder, one of said pin tumblers extending into said keyway and another pin tumbler ending in said plug short of said keyway, and a cam permanently accommodated in said lock and adapted for actuating said other tumbler and releasing it from a locking position.

4. In a lock, a cylinder, a plug with a longitudinal and with an arcuate inaccessible keyway in said cylinder, and pin tumblers locking said plug in said cylinder, different tumblers extending into different ones of said keyways.

5. In a lock, a cylinder, a plug with keyways in said cylinder, pin tumblers locking said plug in said cylinder, different tumblers extending into different ones of said keyways, and a cover on one of said keyways and movable on said lock between positions of closing and of laying free said one keyway, and a key forming part of said cover and extending into another one of said keyways.

6. In a look, a cylinder, a plug with keyways in said cylinder, one of said keyways being permanently inaccessible from the outside of said lock, and pin tumblers locking said plug in said cylinder, diiferent tumblers extending into different ones of said keyways.

'7. In a look, a cylinder, a plug with spaced apart keyways in said cylinder, one of said keyways being disposed in an arc around another, and pin tumblers locking said plug in said cylinder,

different tumblers extending into different'ones of'said keyways.

8. In-a lock adapted to be operated by a key, a plug having a keyway, a bar actuated by said plug by a movement of said plug through a pre-" determined range of movement, means for looking said plug from movement, said means being key operable to release said plug through said predetermined range of movement, and a cover with an opening normally aligned with said keyway, said plug and cover having at all times an unrestricted relative movement or play therebetween from said position of alignment to a second position in which said cover closesthe keyway, said meanswhen not freed by a key checking said relative movement in one direction only at said second'position.

9. A key operated lock, comprising a -bolt,'a plug for actuating said bolt and having a keyway completely receiving the key, said plug being movable after insertion of the proper keyfor actuation of said bolt, a cover normally clearing said keyway, said plug and cover being unrestricted at all times as to a relative movement between a normal position in which said coverclears said keyway and a position in which the cover closes said keyway, and a handle for efiecting said relative movement between said cover and plug into said position of keyway closing and for then moving said plug through the bolt actuating operation.

10. In a lock, a cylinder, a plug with a keyway in said cylinder, a cover closing said keyway, said plug and cover being relatively movably superimposed upon each other, said cover laying said keyway free and clearing it when it is in a normal position of rest relatively to said plug, and said cover outwardly closing said keyway from access thereto upon relative movement between said plug and said cover from said normal position into an actuating position, key freed pin tumblers normally locking said plug in said cylinder and shiftable to a position in which they release said plug relatively to said cylinder, an auxiliary locking mechanism also normally locking said plug to said cylinder, and means, brought into operative relationship with said mechanism by relative movement between said plug and cover into said actuating position to release said auxiliary locking mechanism and thus to disengage said plug from said cylinder at said actuating position provided said tumblers are freed by the proper key.

11. In a look, a cylinder, a plug with a keyway and a cover closing said keyway relatively movably superimposed upon each other in said cylinder, said cover laying said keyway free and clearing it when it is predeterminedly moved relatively to said plug into a normal position of rest, and said cover outwardly closing said'keyway from access thereto upon relative movement between said plug and said cover from said normal position into an actuating position, key freed pin tumblers locking said plug in said cylinder, and shiftable to a position in which they release said plug relatively to said cylinder, auxiliary means also locking said plug to said cylinder, and means forming part of said cover, adapted to release said auxiliary means and serving to disengage said plug from said cylinder after said tumblers have been key freed and when said cover and said plug are relatively shifted into said actuating position. v

12. In a lock, a cylinder, a plug with a keyway, a movable cover closing said keyway, said cover laying said keyway free and clearing it when it is predeterminedly moved relatively to said plug into a' normal position of rest, and said cover outwardly closing said keyway from access thereto upon movement relatively to said plug from said normal position-into an actuating position, key freed pin tumblers locking said plug in said cylinder, and shiftable to a position in which they release said plug relatively to said cylinder, an auxiliary locking mechanism also looking said plug to'said cylinder, and means actuated by said cover, for operating said auxiliary locking mechanism and disengaging said plug from said cylinder when said cover is shifted into said actuating position. v v

. l3.-In a look, a cylinder, a plug with a keyway and 'a movable cover closing said keyway, said coverg laying said-keyway free and clearing it when it is ,predeterminedly moved relatively to said'plug' into a normal position of rest, and said cover outwardly closing said keyway from access thereto upon movement from said normal position into an actuating position, key freed pin tumblers locking said plug in said cylinder, and shiftable to-a position in which they release said plu relatively to said cylinder, a locking mechanism also looking said plug to said cylinder, means on said cover for operating said lock-ing mechanism and disengaging said plug from said cylinder at said actuating position, a handle protruding from said lock and forming part of said cover. 14. In a. look, a cylinder, a plug with a keyway anda rotatable cover closing said keyway, said I cover laying said keyway free and clearing it when it is predeterminedly moved relatively to said plug into a normal position of rest, and said cover outwardly closing said keyway from access thereto upon movement from said normal position into an actuating position, key freed pin tumblers locking said plug in said cylinder, and shiftable to a position in which they release said plug relatively to said cylinder, a locking mechanism also looking said plug. to said cylinder, means forming part of said cover for operating said locking mechanism and disengaging said plug from said cylinder when said cover is shifted into said actuating position, a plate covering the front of said lock and rotatably retaining said cover thereon, and a handle on said cover protruding through an opening in said plate.

15 ,A lock comprising a cylinder, a plug or barrel having a keyway in said cylinder, driver pins in said cylinder, barrel pins facing the keyway in said plug, said driver and barrel pins coacting in pin tumbler fashion when aligned with each other, and a cover plate on said lock outwardly closing said keyway from access thereto when said driver and barrel pins are aligned and when said plug is moved from such position of alignment through a movement of actuation of said lock, and uncovering said keyway for access at a position diiierent from said positions of alignment and movement of-said plug in said cylinder.

16. A lock comprising a cylinder, a plug or barrel having a keyway in said cylinder, driver pins in said cylinder disposed normally at an incline to the keyway in said cylinder, barrel pins in alignment with said keyway in said plug, said driver and barrel pins coacting in pin tumbler fashion when aligned with each other, and a cover plate on said lock outwardly closing said keyway from access thereto when said driver and barrel pins are aligned and when said plug is moved from such position of alignment through a movement for actuating said lock, and uncovering said keyway for access thereto when said keyway and barrel pins are in a normal, vertical position of rest.

1'7. A look comprising a cylinder, a plug with a keyway in said cylinder, driver pins in said cylinder, barrel pins in said plug in alignment with said keyway, said driver and barrel pins coacting in pin tumbler fashion when aligned with each other, a cover plate on said lock having a clearance opening, outwardly closing said keyway from access thereto when said driver and barrel pins are aligned and when said plug moves from such position of alignment through a movement for actuating said lock, and uncovering said keyway for access thereto at a position diflerent from said positions of alignment and movement of said plug in said cylinder, and a handle on said plug protruding from said lock through said clearance opening in said cover plate.

18. In a lock having a movable keyway to receive a proper key for releasing the look when said keyway is in a predetermined position, said lock having a covering means to exclude access to said keyway when said keyway is in said predetermined position, movable means for operating said lock and adapted to be manipulated in a movement between two extreme positions, said keyway being placed by said movable means relatively to said look into said predetermined position intermediate to said extreme positions of said movable means, said covering means laying said keyway bare for insertion or removal of the key in one of said extreme positions, and said movement from the latter extreme position to said predetermined position being free or unchecked.

19. In a look, a cylinder, a movable plug in said cylinder having a keyway for insertion of a key, first and second means locking said plug in said cylinder, said first locking means being releasable by said key, a cover movable from a first position in which it covers said keyway to a second position in which it lays said keyway bare, and a second key means actuated by said cover and releasing said second locking means when said cover is in said first position.

20. In a lock, a cylinder, a movable plug in said cylinder having a keyway, covering means outwardly closing said keyway from access thereto but laying said keyway bare for access in a first position of said plug, and tumblers and drivers arresting movement of said plug in a second position of said plug where said keyway is covered by said means, said plug being freely movable between said first and said second position.

SAMUEL MJILER. 

